Regenerative medicine is the replacement, engineering and regeneration of cells, tissues and organs to gain or restore normal cellular function. Much of the regenerative medicine field is concentrated on cellular replacement therapies, particularly stem cell-based therapies. One property of stem cells that makes them uniquely suited for cell-based applications is their ability to proliferate in culture for prolonged periods of time. This proliferative capacity offers a source of starting material from which to derive sufficient numbers of cells for use in cell-based applications. However, as cells age, even many stem cells grown in culture, their proliferative capacity tends to decrease.
In addition, many adult cells, including cardiomyocytes, neurons, and skeletal muscle, are considered to be postmitotic cells that achieve growth through hypertrophy rather than hyperplasia. Postmitotic cells are unable, or have an extremely limited ability, to divide or regenerate. As such, many organs containing these postmitotic cells are severely restricted in their ability to adequately repair or restore function after any significant injury.
It would be beneficial to provide methods for reinitiating postmitotic cell division to regenerate cells and/or replace damaged cells. Such capabilities would be useful for both in vitro culturing and screening as well as in vivo applications for the treatment of numerous diseases and disorders.